Scaffold machine



P. HUHSMA.

SCAFFOLD MACHINE.

2 SHEETS-SHEET I.

FILED TES, 25, |922.

Patented Jan.. 9, i923.

tra,

" i PETER HOITSMA, `OIE PATERSON, NEW JERSEY.

SCAFFOLD MACHINE.

Application filed February 25, 1922. Serial No. 539,174.

Be it known that I, Pieri-:R Horrsam, a citi- Zen of the United States,residing at Paten son, in the county of Passaic and State of New Jersey,have invented certain new and useful Improveinentsin scaffold Machines,of which the following is a specification.V

This invention relates to climbing supports'and particularly to climbingsupports for use in scaffolding required by workmen in constructing orworking upon a building, and where the scaffolding includes one or more(usually at least two) upriglits spaced from the wall of the building.The object of the invention is to provide a climbing support which willobtain a secure hold on the upright and be at all times proof againstunintentional downward ,y slip ping thereon and which the. workmen`while supported thereby, can operate with facility so as either to climbor descend relatively to the upright and which will further be quitesimple in construction. C

In the accompanying drawings,

Fig. l is a sideelevation of an uprightaiid shows the improved climbingsupport -thereon in vertical section; Fig. 2 is a sectional view on theline 2-72,

Fig. 4, looking toward the right;

Fig. 3 is aplan View of two of the ini-l proved supports arranged on twouprights, which appear in section` vand planking resting on `thesupports iand forming therewith and with the uprights a scaffold;

Fig. @L is a side elevation of what is seen in Fig. 3.

Let a designate one of thefuprights which' will rest on the 'ground andpreferably consist of wooden lengths (as 2 X eps) and further will beprogressively extended up- `wardly -to any desii'ed heightbylap-jointing or otherwise joining the ends of said lengths, the uprightsbeing secured to the building at successive elevations by braces (notshown). Usually there will be at least two of these uprights andtwo ofthe improved supports, one on each upright, and the supports will carryplanking as shown in Fig. `3.'

Each support or supporting structure is constructed as follows, havingreference to the particular example shown in the drawings: Two strips ofangle iron Zr are bent at corresponding points in their lengths so thateach forms an acute angle, one arm b of which is shorter than the otherb2 and is adapted to bear fiat against one upright face ot' the uprighta., so that it stands vertically. c is a horizontal brace which connects"the upper ends of the two arms L, bt. Each thus-bent strip 7) and itsbrace c are rigidly connected together and to the other strip and brace,so as to form what I tei-in the loadecarrying member, by bolts whichpenetrate spacing sleeves e arranged between the two strips Z).

A bolt extending through the two apices of the strips affords a pivotfor a shackle member g, which is astrip of metal bent into the forni ofthe letter U and is adapted -to embrace the upright a, in such mannerthat itsfree ends traverse the latter. Connecting the extremities of themember g is a gripping device 7L adapted to bear againstl the adjoiningface of'the upright and which in order to obtain an effective holdthereon has a biting edge 7L adjacent thereto. as by being square incross-section, said device being kept from turning by being fitted insquare holes in member 1f/. The load-carrying member affords as toitsport-ion b a device which coacts with device z to grip the upright 'whenthe weight of said member is on the shackle member and 7L obtains a holdon the upright. .The shackle is norinally urged upwardliY on bolt as apivot by a spring i which is coiled about the bolt and has one endbearing upon lthe bolt (l and the other end against the bend or iniiei''end of the. shackle. The construction is such that the supportingstructure may easily slip upwardly on the upright but immediatelygravity becomes active to move the structure dmvnwardly. it obtains aperfectly secure grip on the upright on account of the spring. As willappear, the grip thus effected can however be disestablished by pressingdownwardly on the end of the shackle member having the gripping device71.

Given a supporting structure having the foregoing or any other means togrip the upright which is normally freely slidable upwardly but notdownwardly thereon. .l providea lifting means. as follows. which .in thepresent example also in a measure coacts, When not lifting, with saidgripping means to sustain the load. A shackle member is formed by a.strip bent into the shape of `theletter U and having grips /c 7a24connecting its two side portions, said shackle member 4being adapted toembrace the upright so that the latter stands between the two grips; oneof the grips, as s, may be a plain bolt, while the other or relativelyouter one, lag,- is preferably a bolt having a square cross section, andarranged so as to present one of its edges k3 as al biting edge to theupright, being kept against turning by being fitted into square holes inthe shackle. It will be apparent that when both grips engage theopposite faces of the upright and a load is applied to the shackle at apoint thereof nearer one grip (as f) than the other the shackle willgrip the upright and oppose downward movement of the load-positively, ifthe other grip has an effective hold on the upright. A fulcrum supportis providedon the shackle, the same in this linstance consisting of apair of links Z which are pivotally suspended from a cross-bolt mconnecting the sides of the `shackle. and having their lower endsconnected by a bolt a on which is a rollerl la. On the bolt An isfulcrumed a lever o formed by two. metal strips the outer ends o'f whichare rigidly connected byl a bolt [2 and a spacing sleeve Q'penetra-tedby the bolt and arranged between the strips and the inner ends of whichare pivoted on a bolt Q outwardly of the upper ends ot the portions b ofthe load-carrying member, in which the bolt gvis arranged. The shackleis preferably normally urged to turn on the pivot afforded by bolt m inthe direction to elevate the grip 702 by a spring r which is coiledabout the bolt my and has lone end overlappingthe bendl or inner end ofthe shackle and .the other end engaged with a cross bolt s joining thelinks Z.

Operation.' Normally the load is sup-- portedby the means b g; theload-carrying member'b vis at this time kept `'from tilting away fromthe upright on a pivot by the Contact of a with the upright so that tothis extent at least, and even if the gripper y' were moved so` asto'depress'its grip 7a2 and thus cause a release of the gripper, lthelifting means coacts withthe means b-g to sustain the load. To cause thesupporting structure to climb, the operator, who is on the platformafforded by the planking t, de presses the free end of lever o, which atthis time is supported by the means jl, thereby raising theload-carrying member and at the endv of the stroke the means 7) f/assumes a fresh grip on the upright. To rise another stage, the lever iselevated, thereby raising the gripper y' to a new elevation (where itinstantly assumes a fresh grip on the upright both because of thespecified relation of the two grips to each other and to the pivot m.and because of the means r operating to elevate the free end of the gripper), and on nowdepressing the.` lever the lifting operation is repeatedas before.

In descending, the operator sits on the planking t shown in Figs. 3 andl. straddling the upright, with .his feet on the ends of the grippingdevice t. He then raises the lever to cause the upright to be grippedwith a slip grip between g and n', and having released' the shackle gwith his foot and the gripper y' with his free hand allows thesupporting structure to fall, subject to such slip grip, whereupon hereleases the shackle so that' the supporting means becomes locked to theupright at the new or lower elevation. (Or the upward pressure on thelever whereby the slip-grip is controlled may be effected by utilizing arope o which will be lashed to the-upright as shown in Fig. et andpassed around the bolt p of the lever and held under control at its freeend by the operator). Quite independently of the shackle and gripper, t"erefore, the lever o with its gripping device n-n is a factor useful ineffecting controlled descent. Descent may also be effected step by stepthus: by depressing the lever, having first released the gripper, andallowing the gripper to re-engage the upright in the new or lowerposition. aud then, while holding the shackle released with the foot,allowing the supporting structure to descend a stage subject to theoperators control effected through the lever, and finally permitting theshackle to re-engage the upright; and so on, step by step downwardly.

To afford a foot-hold on the shackle y] and a handhold on the gripper jthe ends of the devices It and 7a2 may be prolonged as shown in F ig. 2.

To adapt the shackle g and gripper j to uprights of differentY crosssections additional holes u may be provided in them for the reception ofthe devices 71. and 71:2.

Having thus fully described my invention` what claim as new and desireto secure by Letters Patent is l. In combination, with an upright andVwith a load-carrying member at one side of the upright having means toengage the upright normally freely movable upwardly but not downwardlyon the upright, lifting mechanism including a lever pivotally connectedwith'said member and movable upwardly and downwardly relatively thereto.and means in which the lever is fulcrumed having a gripper engaging thcupright and also normally freely movable upwardly but not downwardlythereon, said lever having means to'bear laterally against the upright.

2. In combination, an upright, a load-carrying member having means toengage the upright normally freely movable upwardly llO but notdownwardly with respect thereto, and lifting means including a shacklehaving' grips engaging opposite faces ofthe upright, a lever piyotallyconnected with said member, a link plvoted to the shackle nearer onegrip than the other und affording a fulcrum support for the lever, and aspring tion to elevate the grip \vhich is remote fromv the link.

In testimonywhereof I aix my signature.

PETER HorrsMA.

